package own.stu.jobgib.playown.alg.leetcode.editor.cn;

//编写程序以 x 为基准分割链表，使得所有小于 x 的节点排在大于或等于 x 的节点之前。如果链表中包含 x，x 只需出现在小于 x 的元素之后(如下所示)。
//分割元素 x 只需处于“右半部分”即可，其不需要被置于左右两部分之间。 
//
// 示例: 
//
// 输入: head = 3->5->8->5->10->2->1, x = 5
//输出: 3->1->2->10->5->5->8
// 
// Related Topics 链表 双指针 
// 👍 55 👎 0



public class PartitionListLcci{
    public static void main(String[] args) {
        Solution solution = new PartitionListLcci().new Solution();
        ListNode l1 = new ListNode(3);
        ListNode l2 = new ListNode(5);
        ListNode l3 = new ListNode(8);
        ListNode l4 = new ListNode(5);
        ListNode l5 = new ListNode(10);
        ListNode l6 = new ListNode(2);
        ListNode l7 = new ListNode(1);
        l1.next = l2;
        l2.next = l3;
        l3.next = l4;
        l4.next = l5;
        l5.next = l6;
        l6.next = l7;

        solution.partition(l1, 5);
    }
    //leetcode submit region begin(Prohibit modification and deletion)
    /**
     * Definition for singly-linked list.
     * public class ListNode {
     *     int val;
     *     ListNode next;
     *     ListNode(int x) { val = x; }
     * }
     */
    class Solution {
        public ListNode partition(ListNode head, int x) {
            if(head == null){
                return head;
            }
            ListNode h1 = new ListNode();
            ListNode h2 = new ListNode();
            ListNode cur = head, c1 = h1, c2 = h2;
            while(cur != null){
                if(cur.val < x){
                    c1.next = cur;
                    c1 = c1.next;
                }else{
                    c2.next = cur;
                    c2 = c2.next;
                }
                cur = cur.next;
            }
            c1.next = h2.next;
            c2.next = null;
            return h1.next;

        }
    }
    //leetcode submit region end(Prohibit modification and deletion)

}
